The Master and his Emissary, By Iain McGilchrist

This remarkable book is a bold thought-experiment,a history, a manifesto – and a mystery. Psychiatrist and philosopher, McGilchrist strides across cultures and histories.

He argues that the ruling traits of any era depend on the dominance of either the left (analytic, detached, factual) or the right (integrative, holistic, "spiritual") hemispheres of the brain.

If he scorns popular clichés based on this division, he also applies a modified form to individual minds and the biases of whole societies, from ancient Greece to modern science.

For him, the "triumph" of the left hemisphere threatens our very survival. It makes a striking fable. But how is it true? As metaphor, or as metaphysics, his great divide at least takes us on an epic ride.